Chronic pain is a worldwide problem with significant physical, psychological, and social impacts. Despite its prevalence and cost, the phenomenon is not well understood. An inductive method of concept analysis was used to study the concept of chronic, non-cancerous pain in adults. A random sample of nursing, psychology, and neurophysiology literature published over a 30-year period (1969 through 1999) was used to generate a consensual definition of chronic pain. The transition in the attributes, antecedents, consequences, related concepts, and surrogate terms of chronic pain is described, and the implications of the findings for practice and research are discussed.